Hop Up acting funny

Hey KWA Forums, I just bought a KWA KM4 Commando. I received it and immediately noticed the hop up wasn't very effective. I looked through the forums and found the threads on cleaning. I took apart the hop up, cleaned the bucking and barrel of all grease/oil and put it back together. I have since noticed 2 things. 1. the hop up seems to walk. Although I haven't done a thorough test, it seems to be moving positions. 2. It seems to take a while before the hop up begins to put spin on the bb. It takes about 10-20 rounds for the hop to start working. After it isn't used for a while, you have to send the same 10-20 rounds down range again to get the hop working again. Anything that could help would be very much appreciated. Thanks! Oh, and I am a new KWA owner and it's great to have such an awesome resource like these forums. Thanks to everyone who regularly checks and is willing to help!

Hey KWA Forums, I just bought a KWA KM4 Commando. I received it and immediately noticed the hop up wasn't very effective. I looked through the forums and found the threads on cleaning. I took apart the hop up, cleaned the bucking and barrel of all grease/oil and put it back together. I have since noticed 2 things. 1. the hop up seems to walk. Although I haven't done a thorough test, it seems to be moving positions. 2. It seems to take a while before the hop up begins to put spin on the bb. It takes about 10-20 rounds for the hop to start working. After it isn't used for a while, you have to send the same 10-20 rounds down range again to get the hop working again. Anything that could help would be very much appreciated. Thanks! Oh, and I am a new KWA owner and it's great to have such an awesome resource like these forums. Thanks to everyone who regularly checks and is willing to help!

Hi Two tone, welcome to the KWA Forums. Her's what I would do.

Tighten the screw on the hop-up adjustment wheel so that it stays set when you turn it

Take a small piece of wire, the same length as the nub is wide, and put it in the hole in the nub. I can almost guarantee you the issue will be solved with this simple mod.

Tighten the screw on the hop-up adjustment wheel so that it stays set when you turn it

Take a small piece of wire, the same length as the nub is wide, and put it in the hole in the nub. I can almost guarantee you the issue will be solved with this simple mod.

Let us know how it works out.

Alright, so I did tighten up the hop and that works just fine. I did add a piece of wire in the nub. It seems to help a little, but I still have to fire a few rounds before I notice the hop up work. Could it be the bbs I'm using? I have been testing it with Lancer Tactical competition grade .25s.

Alright, so I did tighten up the hop and that works just fine. I did add a piece of wire in the nub. It seems to help a little, but I still have to fire a few rounds before I notice the hop up work. Could it be the bbs I'm using? I have been testing it with Lancer Tactical competition grade .25s.

Never heard of them....My guess is there is grease in the bucking though. Take a Q-Tip and swab the bucking while turned fully on. Swab where you see the protrusions inside the inner barrel. Is the Q-Tip dirty? After that I would try some other BBs too.

Interests:Keeping those damn squirrels from putting their filthy little paws on my peaches in my backyard. Oh, Yes. It's not just a hobby, its a passion!!

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Posted 16 October 2013 - 10:54 AM

I agree with gcw.
Even a little bit of grease can cause very poor hop up performance. When new, the bucking and barrel will need frequent thorough cleaning during the break in period where excess factory gear grease can shoot out contaminating the bucking contact surface.

I agree with gcw.
Even a little bit of grease can cause very poor hop up performance. When new, the bucking and barrel will need frequent thorough cleaning during the break in period where excess factory gear grease can shoot out contaminating the bucking contact surface.

gcw360, on 15 October 2013 - 09:10 AM, said:

Never heard of them....My guess is there is grease in the bucking though. Take a Q-Tip and swab the bucking while turned fully on. Swab where you see the protrusions inside the inner barrel. Is the Q-Tip dirty? After that I would try some other BBs too.

Thanks a ton guys! I am trying this all out. I also ordered a 2nd bucking to see if this helps the issue. Again, thanks I really appreciate it!

Interests:Keeping those damn squirrels from putting their filthy little paws on my peaches in my backyard. Oh, Yes. It's not just a hobby, its a passion!!

Country:

Posted 17 October 2013 - 04:07 AM

If cleaning or a new bucking doesn't resolve the issue try using a harder nub. You can insert a piece of wiring or anything hard in the center of the nub cut to length if you can't find anything online.